Abstract
BACKGROUND: This study evaluates WHO guidelines, particularly those integrating health systems guidance (HSG) and clinical practice guideline (CPG), by comparing the AGREE Ⅱ and AGREE-HS tools to identify differences in assessing integrated guidelines (IGs). METHODS: This exploratory evaluation used WHO epidemic guidelines. A comprehensive search in the WHO Institutional Repository for Information Sharing (IRIS) identified CPGs, HSGs, and IGs, which were assessed using AGREE Ⅱ and/or AGREE-HS tools. RESULTS: A total of 157 guidelines (20 CPGs, 101 HSGs, and 36 IGs) were included. CPGs scored significantly higher than IGs with AGREE Ⅱ (P < 0.001), but no significant difference was found using AGREE-HS (P = 0.185). Significant differences were found in multiple domains of AGREE Ⅱ (P < 0.05), including Scope and Purpose, Stakeholder Involvement, and Editorial Independence. AGREE-HS also revealed differences in cost-effectiveness and ethical criteria (P < 0.05). CONCLUSION: CPGs were of significantly higher quality than IGs when assessed with AGREE Ⅱ, while IGs and HSGs showed similar quality with AGREE-HS. Despite consistent overall scores for IGs across both tools, specific item scores varied. These findings underscore the need for more transparent reporting in IGs, particularly regarding developer information, conflicts of interest, and patient guidance. Future work should focus on developing tools that integrate both AGREE Ⅱ and AGREE-HS to improve guideline evaluation. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12874-025-02690-3.